Spark plug



Patented Feb. 1928.

WALTER L. HARTZELL,

or CHICAGO, rumors.

. SPARK PLUG.

, Y Application filed June 16,

My invention relates to spark plugs or ignition devices for internal combustionengines and the like, and it has special relation to the combination of apparatusfor ignition, prim- 6 ing and .carburetion purposes.

One object of my invention is to provide a plurality of separated stationary conductin;- members or terminals, together with a movable conducting member, preferably a 10 metallicball for partially bridging agap between the stationary members.

Another object of my invention is to provide a device of the above-indicated character for preventing fouling of the i nition terminals, which result is accomplis ied by reason of the chafing action of the metallic ball during the operation of the internal combustion engine.

A further objectuof my invention is to provide a spark plug orignition device of such construction as to prevent the fouling or deposit of carbon upon the central insulator portion of the spark plug, such. preventive action being effected by properly guiding an indrawn stream of air over the lower surface of the'insu1ator in close contact therewith. In this way, the insulator is prevented from becoming coated with carbon or lubricating oil, which might cause the electrical charge to leak over the surface of the insulator instead of being concentrated at, the firing point.

Still another object of my invention is to insure the ignition of the charge by removing all dead gasand the like from the vicinity of the ignition terminals and concurrently forcing the live gas to be ignited directly to the firing point.

A further object of my invention is to provide a spark plug wherein the explosive charge in the operating cylinder is prevented from burning inside of the cup or skirt of the spark plug, thereby reducing the heating of the plug as well as the liability of carbon deposit. i

A further objectof my invention is to provide means for inherently guiding a stream of air over or near the normally heated surfaces of the spark plug, particularly the seal between the insulator and theme tallic body, thereby effectively cooling these parts and at the same time gradually increasing the temperature of the indrawn air. By the prevention o'f such heating of the seal, a tight joint is insured and the oracle ing of the insulator is prevented.

fluid being prevented from forming 1922. Serial No. 568,887.

Still another object of my invention is to utilize the air heated in the manner just member that is relatively inverted and constitutesone of the terminals of the spark plug. further object of my invention is to employ an apertured insulator, the aperture registering with the above-mentioned metallic ball, whereby the: engine may be primed, the priming charge being supplied directly to the firing point, but the priming a drop across the firing point by reason 0 the action of the metallic ball. 6

Other objects of my invention will be u derstood from the following description and by reference to the accompanying drawing, Fig. 1 of which is a view in longitudinal section of a spark plug or ignition device constructed in accordance with my invention Fig. 2 and Fig. 3 are transverse sections taken along the lines IIII and III1 II of Fig. 1; Fig. 4 is a view in elevation of'a control apparatus for governing the priming of the internal combustion engine from the drivcrs seat and. also-the amount of air being drawn intothe cylinders through the spark plug, and Fig. 5 is an enlarged sectional view ofa portion of the apparatus that is shown in Fig.

Referring to the drawing, the illustrated apparatus comprises a metallic cup-shaped body orplug 1, which is externally threaded at its lower section or skirt 1 inorder to ecrewinto the combustion chamber of the engine in the usual way, as shown. An insulator member 2, tapered at both ends, is inserted within the plug 1, the lower half of the insulator extending doyvnwardly within the threaded portion or skirt of the plug, while the upper portion extends above the plug body, in accordance with a familiar construction.

A suitable seal 3 is provided at the lowermost contact area of theinsulator 2and the plug body 1, which seal may be of any suitable character. For the purpose of providing an effective cooling of the sealing area without impairing in any manner the eflecan annular groove or upwardly extending recess 4t is provided in the lower side of the plug body 1, surrounding the seal 3. V I

The insulator 2 has a small aperture or passage 5 extending longitudinally therethrough and a perforated tube 6 extends through the aperture 5, the upper end of the tube being enlarged to form a priming cup 7 a suitable distance above the upper end of the insulator 2, while the lower end of the tube 6 is slightly enlarged into a hemi-sphericalcup or seat 16, for a purpose to be set forth. The tube 6 is thus adapted to act as one electrical terminal of the spark plug, a suitable nut 8 being located near the upper end of the tube below the priming cup 7 for permitting the usual type of detachable electrical connection or wire.

A metallic cup shaped member or shell 9, inverted with respect to tne cup-shaped member or skirt 1 of the spark plug, is inserted within the screw-threaded skirt 1 being annularly spaced therefrom by a small distance for a purpose to be set forth. A central portion of the bottom member or cap 9 of the cup 9 is turned upwardly and formed into a hemirspherieal shape or seat .17 just below the correspondingly shaped seat 16 of the conducting tube 6. The cap 9 is adjustably threaded into the shell 9, as shown at 9 for a purpose to be set forth.

A metallic ball 10 is lodged between the two hemi-spherical surfaces in question, the dimensions of the parts being such that, although the ball is freely movable in a ver- I tical direction within predetermined limits,

it cannot normally be dislodged or removed from the cage formed by the two hemir iy spherical. surfaces or seats 16 and 17. The adjustable distance between the nearest surface of the ball and the hemi-sphcrieal surface that it is not in contact with, may correspond to the ordinary or any selec ted sparking distance for the ignition system en'iployed, so that the s )ark, when desired, will jump across the gap between the ball and the spherical surface in question. I

The upper edge 11 of the cup 9 is disposed within the annular recess at of the main body member 1, the cup being mechanically and detachably secured thereto in any suitable manner, as by a. plurality of clips or bent springs 12, disposed around the cylindrical surface of the cup 9, and which yieldingly engage a groove 12 in the inner wall of the screw-tln'eaded portion 1 of the body member 1.

, A good electrical contact is also insured by the pr .ie between the clips 12 and the walls of the groove 12 It will be understood that any other suitable method of mechanically and electrically connecting the cup 9 and the body member 1 may be employed, such as set screws, etc.

By reason of the construction ust described, the vertical distance between the ball 10 and the seat 16 or 1.7that is, the spark ing distance of the plugmay be adjusted as desired, by manually raising or lowering the cap 9*.

Furthermore, the outer surface of the cup member 9 in the vicinity of the lower edge of the screw-threaded portion 1" of the body member 1 is expanded to form a sharp ridge or head 18, whereby an annular nozzle 18 of suitably restricted dimensions is provided between the lower edgeof the screw-threaded portion 1 and the head 18. The purpose of this nozzle arrangement will be hereinafter more fully explained.

It will be noted that, by reason of the construction just described, an air space 14 is provided around the lower portion of the in sulator 2, between it and the walls of the cup member 9, while a smaller annular air space 15 is provided around the outside of the cup member 9, between itand the screwthreaded portion 1 of the main body member 1. Communication between the two spaces or passages 1st and 15 is provided by means of the annular groove 1 in the underside of the body member 1, since the relative position of the cup niembers 1 and'9 is such as to leave the desired ventilating space between the two members in question at the upper edge 11 of the cup 9.

It will be noted that, by reason of the il lustrated construction, the metallic ball 10 is adapted for ignition or sparking purposes by reason of its position with respect to the spherical surfaces or seats 16 and 17, respectively, of the tube 6 and the cup 9. Furthermore, by rea 'on of the provision of the insertion of the tube 6 through the insulator 2, the metallic ball 10 may also be employed for priming purposes when the priming cup 7 is filled.

F or the purpose of governing the flow of gasolene or air through the tube 6, a suitable valve or pct-cock 19, which may be actuated by a handle or lever 20, is provided below the priming cup 7.

The operation of the spark plug device maybe described as follows: During the suction stroke of the engine, the ball 10 is drzuvn down to its lower seat 17 in the bot-' tom of the cup 9, and, consequently, a charge of air is drawn through the tube 6. This charge of air first serves to cool the porcelain insulator 2 internally and, in so doing,

. absorbs a certain amount 0'1" heat itself. The

Also, the entire cup 9 may be readily removed and replaced as desired.

4 over the upper edge of the cup 9 into the small annular space 15. V In passinginto the groove 4, the seal 3 is effectively cooled by reason ofthe proximity-thereof to the air stream.

The air stream. finally is drawn out through the .annularnozzle 18, which, as previously explained, is oi such shape that the incoming air, whichhasfbecn progressively heated by passing over thcvarious elements named p above during, its tortuous course, will be sprayed into thegasolene mix ture in a manner to promote eflicient combustion. Furthermore, sincethe air itself will be somewhat heated, it will assist in vaporizing any particles of gasolene in the cylinderpthus further insuring complete combustion, atjthe proper time. p a a During the compressiongstroke of the engine, the'pressure in theoperatingfcylinder will raise the ball 10 against the upperseat 16 comprising the lower end of the tube 6 and thus will'seal the air :passage'through the tube. IIOWBVGI'yfi small amount offthe gaseous mixture Willbe drawndirectly up to the ball seat in question, thus insuring a good clean mixture at the firing point; The air spaces Hand 15, however, will stillcontain substantially fresh air only and but little, if any, of the combustible mixturewill, therefore, be found in these spaces. Consequently,when the combustion takes place in the cylinder, no burning mixture will sur round the lower portion of the insulator 2 and, consequently, no soot will be formed or no heat willbe generated adjacent to the spark plug inner portions i When the charge is fired by the application of electromotiveforce to the terminals of the ignition circuit, the firing spark will pass from the ball 10, which is maintained in its upper position, as previously stated,to the seat .17 inthe bottom of the cup member 9. As already mentioned,;this distance is selectively adjusted 'to provide the proper jumping distance for the spark.

During the exhaust stroke, thel'ball 10wi1l remain in the upper seat '16 constituting the lower end of the tube 6 until the pressure in the engine cylinder drops sufliciently to allow gravity to return the ball to its lower seat 17. When the ballidrops, any soot; or oil which may have collected upon itdurmg the firing will chafe or rub off, whereby the metallic ball will always be maintained bright and clean. v a

Asregards the priming of the engine, the following method may be employed. The location of the priming cup 7 above the electric terminal member or nut '8 is very convenientin that it allows the necessary priming without in any way disturbing the electrical circuits; Upon pouring gasolene into the priming cup 7,in a manner subseqluently described, a small stream flows t rough the tube 6 directly to the firing point, that is, directly to the seat- 16 just above the; ball 10. However, the stream of gasolene will not be concentrated in the form of adrop across the firing gap because of the (inherent movement of the ball 10 which will break up or prevent any such v formationof drops. In this way, a rich mixture is secured directly at the firing point, rendering the priming actionvery efii'ective, without incurring the liability of directly bridging the firing gap with the priming liqa uid, which action would prevent firing. Reference may nowbefhad to Fig. qshowing the application'ofmy inventlon to an automobile in such manner as to permit ready control of the priming from the drivers seatfl; lThe dashboard 21 of the; automobileis provided with atsuitable gasolene tank or receptacle22 from which a feed pipe 23 runs past the various spark plug devices 1 that are associated With the respective engine I cylinders .28. Opposite each priming cup 7 ofthe apparatus is an outletpipe 24, of insulating material, which fits into the priming cup .7 to readily supply the necessary priming charge Without permitting overflow ofthe gasolene, but not obstructing the passage of air.

lolcontrol the flow of gasolene fol-prime ing purposes, a suitable valve or pet-cock 22 is supplied in the pipe line 23 which may be operated: by a handle 22 extending through the dashboard 21. j a 1 l i To controltheflow of'air to the cylinders either whilepriming or running, a rod 25 extendsthrough the dashboard 21 and parallel to the feed pipe 23 past each valve handle 20. On opposite sides otthe normal po sition ofeach valve handle 20, suitable nuts 26 are threaded upon the 1 rod 25, being spaced at suitable distances to effect movement of each valve from its normal open to its closedy position, or vice verse, by a corres ondin lon itudinal movement of the t g a rod 25 by means of its handle 27, which may be located beyondthe dashboard 21 in a convenient position. j

It will be understood that any other suitable formof apparatusfor readily effecting in lieuof the structure that is illustrated in FigA- 11; a a a y The operation of the priming apparatus may be briefly described as follows: B

moving the handle 22, valve 22? is opene allow ng a small amount of gasolene to pass through tube 23 and-drop 1nto each priming cup 7. The engine, when it begins to turn,

thelpriming action desired may be employed By pulling the handle 27 of the rod 25, the various valve handles 26 upon the spark plug devices are actuated by the nuts 26 from their normal open towards their closed position, whereby the amount of air flowing through the spark plugs and thus the composition of the mixture in the cylinders may be regulated. c

For starting, an exceedingly rich mixture is desirable. After the engine is primed, if it does not start readily, the amount of air being drawn in through the spark plugs may be suitably regulated, or on a steep hill, where a very rich mixture is desirable for a short heavy pull, the amount of air may be cut down. g

I do not wish to be restricted to the specific structural details or arrangement of parts herein set forth, as various m'odifica tions thereof may be effected without departing from the spirit and scope of my invention. I desire, therefore, that only such limitations shall be imposed as are indicated in the appended claims.

I claim as my invention:

1. A spark plug device com-prising a central member having an aperture therethrough, an'outer cup-shaped member enclosing the lower portion of said central member, and a second cup-shaped member disposed in spaced relation within said outer member and forming an annular nozzle therewith.

2. A' spark plug device comprising an apertured insulating member, a cup-shaped member enclosing the lowerportion of said insulating member, and means for guiding air drawn through said insulating member around the lower outer surface thereof to prevent the formation of carbon.

3. A spark plug device comprising an apertured insulating member, an outer cupshaped member enclosing one portion of said insulating member, and a second cup-shaped member inverted with respect to said outer member and disposed therewithin,whereby a charge of air may be drawn through said insulating member, around said one portion thereof within said second cup-shaped'memher, over the edge thereof and between the two cup-shaped members.

i. A spark plug device comprising an insulating member, an outer cup-shaped member enclosing one portion of said insulating member, and a seal between said two memhere, said cup shaped member having an annular groove surrounding said seal.

5. A spark plug device comprising an apertured insulating member, an outer cup shaped member enclosing one portion of said insulating member, a seal between said two members, said cup-shaped member having an annular groove surrounding said seal, and second cup-shaped member inverted with respect to said outer member ma e;

6. A spark plug device for an internal combustion engine comprising an apertured insulating member, an outer cup-shaped member enclosing one portion of said insulating member, a conducting memberextending through said apertured insulating member and constituting a cupped seat at one end, a second cup-shaped member inverted with respect to said outer member and disposed therewithin, said second memher also having a cupped seat, and a metallic ball normally located within one of said seats' and a'dapted'to be actuated to the other seat during the compression stroke of the engine and to act as a sparking-terminal, whereby a charge of live gas to beignited may be drawn directly to the firing point and a charge of air may be drawn through and around's'aid insulating member to pre vent the formation of dead gas in the vicinity of the ignition terminals.

7. A spark plug device for an internal combustion engine comprising an apertured insulating member, an outer cup-shaped member enclosing one portion of said insulating' member, and a second cup-shaped member inverted with respect to said outer member and disposed therewithin, whereby a charge of air may be drawn through said insulating member, around said one portion thereof withmsaid second cup shaped member, over the edge thereof and between the' two cup-shapedmembers, the annular outlet therebetween constituting a. nozzle for spraying the heated charge of air into the engine'pylinder.

8. A spark plug device-for an internal.

combustion engine comprising a central member having an aperture therethrough, an outer cup-shaped member enclosing the lower portion of said central member, and a second cup-shaped member disposed, in spaced relation within said outer member and forming an annular nozzle therewith, whereby acharge of air may be drawn through said aperture and around said cupshaped members to beheated and sprayed through said annular nozzle into the engine cylinder, I

9. A spark plug device comprising an apertured insulating member, an outer cupshaped member enclosing one portion of said insulating membeiya seal; between said two members, said cup-shaped member having an annular groove. surrounding said seal, and, a second cup-shaped member inverted with respect to said outer member @Emdhaifiing'. its; free: edge. disposed with-in; said groove, each cup-shaped member having a helm-spherical seat and a metallic ball normally occupying the seat in said second cupshaped member.

10. The combination with a plurality of engine cylinders, of a plurality of hollow spark plugs secured thereto, remotely-controlled means for simultaneously admitting priming charges to the firing-points of said spark plugs, and remotely-controlled means 10 for simultaneously adjusting the amount of air drawn through said spark plugs.

In testimony whereof, I have hereunto subscribed my namethis 21st day of August,

WALTER L. HARTZELL. 

